Once a computer system has been established, and the capabilities exist for the kind of data manipulation which could produce either a book catalog, with as many access points as seem desirable, or catalog cards if desired, the next question to be resolved is whether a book catalog is an economically feasible substitute for catalog cards. The advantages and disadvantages of both card catalog and book catalogs are considered. It is concluded that it is not economically sound to plan on a book catalog unless many copies are required, or the unusually high per-copy costs for a small number can be justified. (Author/MM)